1. Field of the Invention
The present invention relates to a method for fabricating a gallium nitride-based semiconductor electronic device.
2. Related Background Art    Patent Literature 1 (Japanese Unexamined Patent Application Publication No. 2007-158133) discloses a laser lift-off process. A light-emitting region, an n-type layer, and a p-type layer are formed on a sapphire substrate. An n-type silicon substrate is then prepared, and conductive multilayer films are vapor-deposited on two surfaces of the substrate. Subsequently, an electrode on the p-type layer and the conductive multilayer film on the n-type silicon substrate are hot-pressed at a temperature of 300° C. to coalesce the two substrates. The back surface of the sapphire substrate is then irradiated with laser light so that GaN on the surface of the n-type layer is decomposed. The sapphire substrate is then removed by a lift-off process.    Patent Literature 2 (Japanese Unexamined Patent Application Publication No. 2006-100801) discloses a group-III nitride semiconductor element having a structure exhibiting improved reverse-voltage resistance. The group-III nitride semiconductor element is provided on a GaN substrate.    Non-Patent Literature 1 (The 69th Academic Meeting of The Japan Society of Applied Physics, Preliminary Draft, Autumn 2008, Chubu University, 5a-CA-9) discloses re-lamination of a homoepitaxial GaN layer on a GaN substrate to a Si substrate.